The present invention is directed to a tool lifting machine for facilitating the transport, transfer, or otherwise manipulation of heavy tools in an ergonomically-acceptable fashion. More particularly, the present invention is directed to a machine for transferring large milling cutters between a storage position and an installed position in a milling machine with little effort required by an operator.
Ergonomics are an important consideration in many modern day manufacturing environments. That is, most manufacturing-related processes are now examined to make sure that the effort exerted in their performance is not overly burdensome on an operator. A variety of process-related factors may be considered such as, for example, repetitive motion, the required position of the operators limbs and/or body, and the size, shape and/or weight of components and/or tools that must be manipulated by the operator.
While many of these concerns may be obviated through well thought out process and/or equipment design, some cannot. For example, certain process components or tools simply cannot be sufficiently reduced in size and/or weight to achieve a particular ergonomic target. A process employing these components or tools may, therefore, be difficult for an operator to perform—whether on a repetitive basis or otherwise. Similarly, when an operator is required to manipulate large and/or heavy components or tools, there is sometimes a risk of harm to the operator and/or of damage to the components or tools.
Many types of specialized process assisting equipment have been developed to assist operators in performing what would otherwise be difficult tasks. However, to Applicant's knowledge, no such equipment exists for transferring large machine tools, such as milling cutters, from a storage location to an operating position within a milling machine spindle.
While there may be no such need with respect to small milling cutters, there is such a need for larger cutters. Large milling cutters differ considerably from the small fluted end mills familiar to many. These larger cutters generally comprise a cutter body portion of significant diameter into which is mounted a plurality of cutting elements, thereby allowing for the removal of material from a considerable surface area of a work piece in a single pass. The body portion is typically manufactured of a hardened steel and has extending from one end a tapered shaft that is adapted to be received and retained by a milling machine spindle. As a result of this design, such milling cutters are often very heavy, unbalanced, and difficult to grasp and hold.
In addition to the size and weight of such milling cutters, there is also the problem of manipulating the cutter during installation. Large milling cutters are commonly stored on a rack or cart when not in use. Often, the cutters are suspended in the rack by the larger diameter cutter body—which generally results in the tapered shaft portion extending (vertically) downward toward the ground. Unfortunately, in the case of, for example, a horizontal milling machine, this storage position is rotated 90° from the operating position of the cutter. More particularly, in such a milling machine, the spindle receives the shaft of the cutter in a substantially horizontal position. Consequently, subsequent to removing the cutter from the rack, it must be rotated by the operator prior to being introduced to the spindle of such a machine.
As such, it can be seen that a machine for removing such a milling cutter from a storage rack, rotating the cutter into operating position, and installing the cutter to a milling machine spindle—with little effort required on the part of an operator—would be highly desirable. Preferably, such a machine would be able to manipulate milling cutters for one or more milling machines, regardless of the diameter of the cutter body. Such a machine would greatly reduce the stresses put on an operator during a milling cutter installation/removal procedure, and may reduce tool change time as well. An ergonomic tool lifting machine of the present invention satisfies these requirements.